Reductio ad absurdum — what if only one person were presymptomatic, who had a “lot of spread”? Would it still be worthwhile to lock down and mask the entire population of the United States, and to shutter its businesses and places of worship? Clearly, there are many more than one, but my point is, that number is relevant to policy decisions.
The more relevant number is 600k Covid deaths.
It would be foolish not to address the population most responsible for spreading the disease no matter how big it is.